CHAPTER XII 

 DEFENSIVE FERMENTS 



INTRODUCTION. 

 SPECIFICITY OF FERMENTS. 

 IMMUNE FERMENTS. 

 FERMENTS IN THE BLOOD. 



FERMENT-ANTIFERMENT BALANCE. 



ANTIFERMENT. 



THE ABDERHALDEN TEST. 



Introduction. The relation of ferments to immunity and ana- 

 phylaxis has long been the subject of discussion. In the chapters on 

 special immune bodies we have discussed the. similarities and differences 

 between ferments or enzymes and antibodies. Special consideration has 

 been given to certain phases of ferment activity, particularly in the 

 chapter on Cellular Resistance and that on Hypersusceptibility. Ap- 

 parently the first work to prove that digestion takes place outside the 

 intestinal tract was that of Hammersten, who showed in 1885 that 

 washed leucocytes increase the solubility of fibrin. This was followed 

 by more comprehensive studies on cellular ferments as have been pre- 

 viously outlined (page 167). In addition to those ferments which exist 

 in the cells, ferments have been discovered in the blood and other circu- 

 lating body fluids. Therefore, we may classify the ferments as intra- 

 cellular and extracellular. The scope of this book is too limited to 

 permit of any general discussion of ferments as a group and the 

 reader is referred to the sections on this subject in Wells' " Chemical 

 Pathology." Many of the earlier workers assumed that ferments in 

 the body fluids are derived essentially from the leucocytes. A recent study 

 of considerable significance is that of Boldyreff. He maintains that the 

 glands of the alimentary canal, with the exception of those of the 

 stomach, are not at rest between the digestive periods and that they 

 exhibit a periodic function. As a result of this periodicity, secretions 

 are discharged into the empty intestine from which they are absorbed 

 and at times are demonstrable in the blood. Van Calcar claims that 

 the leucocytes are incapable of producing their own ferments and that 

 these ferments are derived from special glands. He found that extir- 

 pation of the stomach is followed by a decrease or absence of that 

 ferment of the leucocytes which acts best in acid medium and that 

 extirpation of the pancreas similarly is followed by a loss of tryptic 

 powers on the part of the leucocytes. Abderhalden believes that invertin 

 also is derived from the intestinal glands. This conception would indi- 

 cate that the appearance of ferments in the circulating body fluids is to 

 be regarded as a mobilization of ferments from the cells which 

 formed them. 



Specificity of Ferments. It is well known that the body ferments 

 act specifically upon certain chemical substances, as exemplified by the 



245 



